Carburetor



Dec., 30, 1930o v o. H. ENslGN 1,737,148

CARBURETOR F-iled June 11. 1924 Patented Dec. 3l), 1930 v'UNITED STATES PATENT OFFICE ORVILLE H. ENSIGN, OIE PASADENA, CALIFORNIA, ASSIGNOR TO EN SIGN CARI-BURETOR COMPANY, F LOS ANGELES, CALIFORNIA, yA CORPORATION 0F CALIFORNIA CARBURETOR Application led June 11, 1924. Serial No. 719,297.

My inventionlrelates to that class of carburetors for internal combustion engines A wherein a depression caused by the *main air stream is communicated through a fuel passage to the fuel for the purpose of proportioning the flow of fuel to air. y It is well known that in carburetors of this type, a small air'bleed opening into said fuel passage will materially change the proportion of fuel to air. An object of this invention is to automatically apply such an air bleed to the fuel passage to thin the mixture, and to automatically limit the application of such air bleed to such temperatures of the mixture that will allow the successful operation of the engine with the thin mixtures resulting from the application of this air bleed.

It is also well known that when the Iengine is cold it is necessary that the supply of air to the carburetor be decreased, or the supply of gasoline correspondingly increased, unless the mixture is supplied to the engine in a state of high vaporization; and that in such cases even though the engine is cold, it-will operate satisfactorily if supplied with a thin highly vaporized heated mixture. I

An object of this invention is to pr0v1de a carburetor with novel automatic means whereby the operation of an economizer air bleed on a carburetor or fuel converter is limited or controlled by the temperature of the mixture passing through such carburetor, so that such air bleed can be made practicable.

Another object is to provide novel automatic means whereby maximum economy and operation is obtained through the ordinary driving range of an automobile, without the operator having to specially adjust the mixture by a choke or other means during the warming up period. Y

A further object is to provide means to automatically modify the mixture of a self-heating type carburetor for purposes of economy and to limit such modification to the temperature of the mixture passing through the carburetor that makes practical such economy.

The invention comprises the parts and combination and arrangement of parts hereinafter more specifically referred to.

Although I have shown my invention as applied to a carburetor known as a fuel converter,'the broad principles of this invention may be applied to any standard form of carburetor.

Other objects, advantages and features-of invention may appear from the accompanying drawing, the subjoined detail description and the appended claims.

The accompanying drawing illustrates the invention as applied to a fuel converterltype of carburetor.

Figure l is a fragmental verticallsect'ion on irregular line acl-ml, Fig. 2, through a carburetor constructed in accordance with this invention, and showing the throttle Valve in position for idling and the fuel at rest.

'line m3, Fig. 2.

Fig. 4. is a fragmental horizontal section Fig. 2 is a condensed fragmental plan on line :M -m4, Fig. 3 showing the thermostat valve passage partially open under inluence ofthe heated mixture passing the.V

throttle. A

The invention may be carried out with various types and forms of carburet'ors or mixing valves or devices that will properly proportion the fuel and air for the mixture, and is shown as attached to a carburetor in which a portion of the mixture, the fuel and the air is diverted froma mixture passage to a place where combustion is eifectedto heat the mixture.

The proportioning and mixing chamber 1 receives its air through theair inlet 2, and its Aliquid fuel through the fuel jet 3 in a. well known manner, and` producesa mixturey of more or less broken-up fuel and air, which mixture is emitted from said mixing chamber into an inclined mixture passage 4 that has an abrupt upward bend at 5 and there communicates with an upwardly directed limb or riser 6 to the throttle cham- `ber 7 which is separated by the throttle 8 on shaft 8 from the diffusion chamber 9.

The liquid fuel and air are supplied to the mixture chamber 1 by suitable proportioning means, as the constant level fuel supply chamber 10 and the air inlet 2, operating in conjunction With each other and the engine suction, whereby liquid fuel and air are supplied in proportions to produce an explosive mixture; so that the final product issuing from the diusion chamber 9 is adapted for complete combustion Without the addition of either air or fuel.

Liquid fuel is supplied to the fuel cham ber 10 through the usual fuel connections at 11 controlled by valve 12, the oat 13 in the supply chamber cooperating to maintain the fuel in said chamber at a constant level 11i, and the fuel being delivered fronithe supply chamber 10 through the fuel orifice 15 into the fuel passage 16 from which it is delivered to the main air stream of the carburetor through the fuel jet 3.

rlhe combustion chamber 17 is suitably supplied With fuel and air from the mixture passage 4 in any Well known Way, as through the fuel passage 18, l', and the air supply pipes 19, 19"; the mixture in the combustion chamber 17 being fired the usual spark pluo 2O and the hot gases Withdrawn from the combustion chamber and returned to the mixture at the diffusion lchamber 9 through the gas flue S31, i the usual Way with the type of carburetor shown.

rlhis invention resides in ai'ftematically opening and closing, at predetermined manifold depressions, an air bleed eoinprising a passage 2:?, that is open at one. to the atmosphere as at 22 and is elected at its other end to the enlargement s at E23, of the fuel passage 16; and in also automatically controlling the operation or application of said air bleed by thermostatic means A. The passage 22 is normally closed by a gravity check valve 24e and admits air tothe fuel passage 16., and operates in 'i manner as set forth in my eo-r plication, `filed May 1924, o '511,913, except as modified or centrolled by said thermostatic means A. i

The thermostatic means is preferably mounted in a bore 25 formed .t boss 26 extending from the side Walls of 'the :riser 6; and comprises a tnermostatie member such as a strip or ribbon of laminatedtlier mostatic metal 27 Wound in a helix as shown in lligs. 1 and 3. @ne end ef the 'n Tuben 9,? is fixed the bore E25 h ci by a pin 28 to a recitar ug 29 Which is ixed in the re by a so that passes 'through such and the 2f. A

valve plug 31 having an e to the other end of saii seal 34: is driven ir.

is not used in the combustion chamber is,

diverted into 'the gas fluye by Way of the ports c and c", the annulus d and the flue ports e. rlhe throttle 8 is perforated by the small hole Y) to maintain draft in the gas line 21 during idling of the engine.

1n operation the carburetor being operably connected to manifold of an engine, not shown, the suction of the engine' will draw in air at the air inlet 2 of the mixing chamber 1, and the flow of air through such Achamber will cause, about the jets 3 a depression Wliich Will be communicated through the fuel passage 16 to its enlargement 23 Where such depression acts upon the fuelin the fuel passage to cause fuel to flow through the fuel orifice 15, fuel passage 16 through the fuel jets 3 thus putting the carburetor in normal operation.

Fuel will then be more or less raporized or atomized the whirling motionA of the air in the ir'xing chamber 1 and the mixture will issue 't refrom to the mixture passage l flowing are ind the bend 5 through the limb il past the throttle 8 to the dilfusion chamber 9 and thence to the manifold.

lWith the present-day' gasoline'euly a por- -ion of the f l becomes vagorized by atomiaation or erwise Without heat` therefore much of el falls to the floor of the passage el.

Combustion in chamber 1? heats the carburetor and the mixture. The fuel for supplying this combustion will be taken from the fuel on the floor of the mixture passage l and Will fioul through the passage 18 and issue from the nozzle 18 into the combustion chamber 17. fair Will flow through the passage 19 and mingle with the fuel issuing 18. .lir Will also dowthrough the passage 19'" and over the top of the distributor a issuing thence into the combustion chamber thereby sustaining combustion.

gnition occurs at the spark plug electrode 20 from a suitable ignition circuit not shown. The products of'combustion from the combastion chamber 17 are Withdrawn through Ehe gas line te the diiusion chamber 9: and when the throttle is closed the flow is largely through the small -hole l) in the throttle 8 and When the throttle is open as shown in Fig. 2, th flow is direct to the diffusion chamber a i re the hot gases nlingle with the mixture eh has passed in the normal Bou i wem-ie After operating for a short time, the floor of the passage 4 and the portion of the passage around the bend 5 and through the limb (S become heated so that vaporization of much of the fuel takes place by contact with the walls of the passage, and the heat from the combustion chamber is conducted by the passage walls to the walls of the throttle chamber 7 and the diffusion chamber 9 and heats the same materially.

Further heat is communicated to the upper end of passage 4c by the mixture coming in contact with the hot lower portions of the mixture passage 4 and the gas flue 21.

But at all times there are portions of the heavy ends of the fuel, which do not vaporize at the temperatures available by the e means above described, and these portions will enter the ports c, c and pass through the annulus d and the holes@ in the gas iue and thus be delivered directly into the red hot products of combustion leaving the combustion chamber and are fully vaporized within the gas flue 21.

This operation .reaches this stage very shortly after starting the cold carburetor, enabling the carburetor withoutthe operation of the economizer bleed to goimmediately into full, iexible operation of engine even in very cold Weather.

ln the present invention, the economizer valve 37 is held closed on its seat by the tension of the spring 38 when the engine is at rest, and the spring 38 is sufficiently powerf ul to close the economizer valve 37 at an engine ispeed corresponding to a predetermined controlled road speed on a level road at say about 40 miles per hour.

At all road controlled speeds below the predetermined speed this economizer valve will be open. At all speeds above, it will be closed; but at any controlled speed below the limit of about forty miles an hour upon opening the throttle to accelerate the car, the

economizer valve instantly closes and will remain closed until the new7 controlled speed is attained when such Valve will open again and allow air, to enter the economizer air bleed 22 to the enlargement 23 of the fuel passage 16, thereby materially thinning the mixture in the carburetor. i

rlhe depression on Athe engine side of the throttle is suiicient at all of the above-mentioned controlled engine speeds to draw the piston operated economizer valve 37 away from'its .seat and said depression is applied through the tube 36 and the valve 31.

The thermostat unit A which operates to rotate the valve 31 within its bore, is normally adjusted to begin to open the valve 31 at a ten'iperature that will allow flexible opertion of the car with the bleed 22 open. Thus in starting out with a cold motor and cold carburetor the air bleed remains closed, and normal full power mixture is maintained until such timeV as the temperature of the mixture becomes high enough toI allow the car to operate successfully with the air bleed open when the Valve 31 is opened thereby allowing-operation of the economizer air valve 37.

The normal operating characteristics of the carburetor with the combustion` chamber is such as to give a higher mixture temperature at the throttle when the motor is idling; at which time the motor is at its lowest operating temperature, and at the same time the carburetor is raising the temperature of the mixture for applying the load without losing flexibility.

On the contrary when the motor is operated at full load and at wide open throttle, the mixture temperature issuing at the throttle is-at its lowest, thus giving full power with a cooler mixture and warmer engine, at which time if the heat were derived from the engine the power would be restricted. It is thereforeseen that this thermostatallows operation of the air bleed 22 to thin or enrich the mixture without regard to the engine temperature; operating solely by the mixture temperature from heat generated within thecarburetor itself.

Should the carburetor be supplied with hot air from a stove or the exhaust pipeior heated by other means from the engine, the economizer will only operate to thin the mixture when the mixture temperature is such as to make it practical to use such thin mixture.-

I claim:

1. In combination with a carburetor, an economizer air bleedvalve connected and adapted tobe operated by predetermined manifold depression for controlling the admission of air into the fuel passage of the carburetor; a thermostat controlled valve positioned to be influenced by the temperature of the mixture to operatively connect and disconnect from the manifold the economizer valve at predetermined mixture temperatures.

2. In combination with a carburetor, `an economizer air bleed valve connected to and .adapted to be operated by predetermined bir c ose said passage valve.

the mixture temperature to open and 4. A carburetor provided with' an economizer air bleed valve operably connected to the engine side of the throttle by a passage for controlling admission of air into the fuel passage of the Carburetor; a valve to open -and close said passage; and thermostatic means to open and close said passage valve.

5. A carburetor provided With a fuel supply chamber and a fuel passage from said supply chamber to the main air stream; an air passage connected to said fuel passage; valve means operable by manifold depressions controlling the entrance of air into said fuel passage through said air passage; and thermostatie means to allow operation of said manifold depression operated means only at predetermined temperatures.

6. A carburetor adapted to be attached to an engine manifold having a fuel supply .chamber and a fuel passage from said supply chamber to the main air stream provided w1th an enlargement; an air passage coni nected to the enlargement of said fuel passage; means operable by predetermined manifold depressions controlling the entrance of air into said enlargement; and a thermostatic device positioned to be operably influenced by predetermined mixture temperatures to further control the operavvtion of said means.

7. A carburetor provided with a fuel supply chamber and a fuel passage from said supply chamber to the main air stream; an air passage connected to said fuel passage; a gravity check valve controlling said air passage; valve means operable by manifold depressions controlling the entrance of air into said fuel passage; and thermostatic means to allow operation of said manifold depression operated means only at predetermined temperatures.

8. A carburetor adapted to be attached to a throttle controlled engine manifold, said carburetor havingI a supply chamber and a fuel passage from said supply chamber to the main air stream; an air passage connected to said fuel passage; means operable by manifold depressions controlling the entrance of air into said passage comprising piston and a passage connecting one side of said piston to the manifold above the throttie; and thermostatic device comprising a thermostatic member non-rotatably mounted at one end and having a rotatable valve plug mounted in its other end; said valve plug having an opening adapted to open and close at a predetermined temperature the passage connecting one side of the piston to 'the manifolzl.

- El. A carburetor provided with a fuel supply chamber and a fuel passage from said supplv chamber to the main air stream;

` connected to said fuel passage; a

spring' depressed piston normally closing said air passage; a passage connecting one side of said piston to the air stream above the throttle of the carburetor; and means to automatically open and close the passage from the piston to the engine side of the throttle.

10. A carburetor provided with a fuel passage; a valve controlled economizer air bleed opening into said fuel passage; means operable by manifold depressions to open said valve; and automatic means to prevent operation of said valve at predetermined temperatures. l

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 4th day of June, 1924.

ORVILLE H. ENSIGN. 

